From 05734ca2a8f76c9eb3890b3c9dfc3467f03105c1 Mon Sep 17 00:00:00 2001 From: Jani Nikula Date: Tue, 5 Oct 2021 20:56:36 +0300 Subject: [PATCH] drm/i915/bios: gracefully disable dual eDP for now MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit For the time being, neither the power sequencer nor the backlight code properly support two eDP panels simultaneously. While the software states will be independent, the same sets of registers will be used for both eDP panels, clobbering the hardware state and leading to errors. Gracefully disable dual eDP until proper support has been added. Cc: José Roberto de Souza Cc: Uma Shankar Cc: Ville Syrjälä Cc: Swati Sharma Reviewed-by: José Roberto de Souza Acked-by: Ville Syrjälä Tested-by: Swati Sharma Signed-off-by: Jani Nikula Link: https://patchwork.freedesktop.org/patch/msgid/20211005175636.24669-1-jani.nikula@intel.com --- drivers/gpu/drm/i915/display/intel_bios.c | 47 +++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c index f9776ca85de3..b99907c656bb 100644 --- a/drivers/gpu/drm/i915/display/intel_bios.c +++ b/drivers/gpu/drm/i915/display/intel_bios.c @@ -1930,6 +1930,50 @@ static int _intel_bios_max_tmds_clock(const struct intel_bios_encoder_data *devd } } +static enum port get_edp_port(struct drm_i915_private *i915) +{ + const struct intel_bios_encoder_data *devdata; + enum port port; + + for_each_port(port) { + devdata = i915->vbt.ports[port]; + + if (devdata && intel_bios_encoder_supports_edp(devdata)) + return port; + } + + return PORT_NONE; +} + +/* + * FIXME: The power sequencer and backlight code currently do not support more + * than one set registers, at least not on anything other than VLV/CHV. It will + * clobber the registers. As a temporary workaround, gracefully prevent more + * than one eDP from being registered. + */ +static void sanitize_dual_edp(struct intel_bios_encoder_data *devdata, + enum port port) +{ + struct drm_i915_private *i915 = devdata->i915; + struct child_device_config *child = &devdata->child; + enum port p; + + /* CHV might not clobber PPS registers. */ + if (IS_CHERRYVIEW(i915)) + return; + + p = get_edp_port(i915); + if (p == PORT_NONE) + return; + + drm_dbg_kms(&i915->drm, "both ports %c and %c configured as eDP, " + "disabling port %c eDP\n", port_name(p), port_name(port), + port_name(port)); + + child->device_type &= ~DEVICE_TYPE_DISPLAYPORT_OUTPUT; + child->device_type &= ~DEVICE_TYPE_INTERNAL_CONNECTOR; +} + static bool is_port_valid(struct drm_i915_private *i915, enum port port) { /* @@ -1987,6 +2031,9 @@ static void parse_ddi_port(struct drm_i915_private *i915, supports_typec_usb, supports_tbt, devdata->dsc != NULL); + if (is_edp) + sanitize_dual_edp(devdata, port); + if (is_dvi) sanitize_ddc_pin(devdata, port); -- 2.11.0